Modern baking plants are capable of producing large quantities of baked foodstuffs, for examples, cookies, crackers, and the like. However, in order to attain full operating efficiencies in the baking operations conducted in these plants, the article handling and packaging systems used to handle and package these articles, respectively, must be constructed to efficiently and quickly process these large quantities of articles. The article handling and packaging system thus needs to move the articles away from the baking oven toward a downstream packaging machine while simultaneously ordering and metering the articles as they pass along a path of travel defined by the handling and packaging system, for example forming the articles into separate article lanes and then forming spaced rows of articles therefrom such that the articles will be packaged efficiently and quickly.
Due to the great numbers of baked foodstuffs produced in modern baking plants, however, coupled with the limitations of existing article handling and packaging systems technology, the problem arises that baked foodstuffs can be produced much more quickly than they can be efficiently handled. Moreover, it is desirable to have as little human handling of the articles as possible in order to prevent product breakage or damage which is undesirable, as well as for health and safety reasons such that any potential health risks to the end consumer of the article are minimized. Thus the need exists to be able to control the articles, form them as desired for packaging configurations, package the articles, and ship them quickly, efficiently, and economically.
One of the problems in controlling articles to be packaged is to move the articles rapidly along an article handling and packaging system, yet space them so that the articles can be individually controlled and thus positioned in desired spaced relationships not only with respect to one another, but also with respect to the packaging machine such that the desired article configurations are packaged quickly. The sorting apparatus for food items of U.S. Pat. No. 4,535,881 to Mims represents an early attempt to respond to this need by providing a conveying and sorting apparatus for sorting food items into parallel lines of uniformly spaced food items.
Two rotary members are provided by the device of Mims for each line, or lane, of food items. Each of the rotary members is positioned above and perpendicularly with respect to the line of articles, and is constructed to have a central hub with a plurality of retractable spokes or fingers which extend radially therefrom, and move reciprocally from an extended position into a retracted belt engaging position. As constructed, the sorting apparatus of Mims thus will always have a minimum of two of these spokes in contact with the surface of the conveyor belt at any one time. The food items passed along the conveyor will engage the spokes of the rotary members much as a chain engages the teeth of a sprocket to maintain a uniform spacing between the food items.
A drawback of the Mims device, however, is that at least two, and oftentimes four of the spaced radial fingers or spokes of the device are engaged with the surface of the conveyor belt. This, of necessity, limits the speed with which the machine can operate as the mechanical motion of reciprocating the fingers must be accommodated without moving them so quickly as to cause them to become jammed or damaged, and may also allow the spokes to come down and strike or land on top of an article which is otherwise out of position on the conveyor such that the article is damaged or destroyed, and which may also damage the indexing device itself.
Another drawback with the device of Mims is that it does not appear to be adapted for the quick changeover for handling differing product shapes, sizes or packaging configurations as disassembly of the device will be required in order to change the spacing of the spokes to accommodate a differently sized article. For example, in order to accommodate articles of a certain size, the spokes of the Mims device must be spaced far enough apart to allow successive ones of the articles to be received by a respective pair of the fingers of the indexing device. If these articles become significantly larger, for example, then as a first set of fingers engages an article, the second set of fingers will tend to come down into engagement with the topmost surface of the article. If the article is significantly smaller, then it may be allowed to pass between a pair of fingers if spaced too widely apart, and will likely also require that the rotary indexing device be run at a very fast rate of speed in order to allow for an efficient operation of the article handling and packaging system, i.e. obtaining a satisfactory production yield.
Lastly, another potential drawback with the Mims device is that the conveyor belt on which the articles are being carried beneath the indexing device must be moved very quickly in order to allow the articles to be spaced as they leave the set of fingers with which they were engaged as nothing is disclosed in Mims which would otherwise indicate that the speed of the indexing device may be varied in response to a downstream packaging machine, for example.
Another approach to solving the problem of spacing articles carried along a conveyor on an article handling and packaging system is disclosed in U.S. Pat. No. 5,303,881 to Haley, which discloses a spacer system for a surface conveyor. Haley provides a metering device which is constructed and arranged to engage and release foodstuffs being moved along a path of travel on a conveyor belt such that relative positions of the foodstuffs on the conveyor belt are spaced at a predetermined interval, or intervals. This is accomplished by providing a spaced pair of fingers which extend in the downstream direction and which are reciprocated up and down to allow articles to pass therebeneath. The fingers of the Haley device come down, preferably, in the space located between abutting articles, for example in a gap created between the articles within a queue of articles formed on the conveyor, upstream of the device.
A drawback with the device of Haley, however, is that as the fingers of the device are reciprocated up and down, this limits the speed with which the fingers can be moved in association with the speed of the conveyor belt to allow a sufficient amount of time for the articles to pass therebeneath and to be spaced thereby without otherwise striking and destroying articles as they are passed through the system. Moreover, the device of Haley is not well suited for use with all types of articles, for example chocolate covered or enrobed cookies and snack cakes. For example, as the spaced fingers of the Haley device are moved downward they may strike the article, especially if the article is relatively soft, for example a soft baked cookie, with enough force that they may become imbedded in the article. The possibility also exists that as the fingers pass over and along the surface of the article they may either scrape off or become fouled with the covering or icing on the surface of the article. In either instance, this may cause the feed conveyor and/or the spacer device to become jammed by the article(s), will likely damage the articles, and/or may damage the device itself.
Both, the device of Haley and the device of Mims described above, are constructed to index a uniformly sized and shaped article. In Haley, this uniformly shaped article must be relatively flat so that when and if the fingers land on the top surface of an article being spaced thereby, the fingers are allowed to slide over as the article as it continues to pass therebeneath, whereupon the fingers will then fall into the gap between the article and the next succeeding article. Neither of the devices to Haley, nor to Mims, however, are constructed and arranged to either form or control a second queue of articles therewith. For example, neither device, once it spaces an article and releases same along the path of travel, is adapted to selectively control the position of selected articles along the path of travel such that the possibility arises that the articles may become spaced too closely together, or too far from one another with a resulting inefficiency in packaging machine operation because a controlled flow of articles is not being fed to the downstream packaging machine. This may result in an undesirable increase in production costs and packaging machine wear due to having to stop and start the packaging machine because of either too many or too few articles being available for packaging.
What appears to be needed, but is seemingly unavailable in the art, is a simple and reliable article metering device that will allow for improved production rates, and thus improved operating efficiencies and production yields, in use. Moreover, the need for such an improved article metering device exists which will provide a flexible device, and a metering method, for handling a variety of article types and sizes easily and efficiently, and which provides an adequate degree of flexibility in usage so that it can be quickly changed over to handle articles of a variety of sizes and shapes. It is also desirable that such an article metering device not engage the conveyor belt passing therebeneath, and be constructed to control the relative positions of an accumulate queue of articles as they are passed therethrough in order to ensure that proper spacing of the articles is maintained as they pass along the article handling and packaging system. Lastly, there is a need for an improved article metering device, and an article metering method using such a device which does not rely upon spokes or fingers which are spring-loaded or mechanically driven into engagement with a belt and which are then retracted so as to minimize the likelihood of mechanical wear or breakage to the device, and which also will tend not to damage the articles if the articles are struck by the device as they are being processed.